npm install --global expo-cli

expo init sns

- Managed workflow -----
❯ blank                 a minimal app as clean as an empty canvas 
  blank (TypeScript)    same as blank but with TypeScript configuration 
  tabs (TypeScript)     several example screens and tabs using react-navigation

- api サーバーとの通信や外部APIを叩く処理
- assets 画像関連
- components 共通コンポーネント
- context useContext関連
- hooks customHooks関連
- navigation react-navigation関連
- screens 各ページとページ毎のcomponent
  |- Home
   |- atom
   |- molecules
   |- organisms
- App.js main 

expo install @react-navigation/native @react-navigation/bottom-tabs
expo install react-native-gesture-handler react-native-reanimated react-native-screens react-native-safe-area-context @react-native-community/masked-view
expo install react-native-elements react-native-vector-icons
expo install axios form-data

//[new] screens/HomeScreen.js
import React from "react";
import { View, Text, StyleSheet } from "react-native";

const HomeScreen = () => {
  return (
    <View style={styles.container}>
      <Text>HomeScreen</Text>
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    justifyContent: "center",
    alignSelf: "center",
    flex: 1,
  },
});
export default HomeScreen;

// [new] navigation/AppNavigator.js
import React from "react";
import { NavigationContainer } from "@react-navigation/native";
import { createBottomTabNavigator } from "@react-navigation/bottom-tabs";
import HomeScreen from "../screens/HomeScreen";
import AccountScreen from "../screens/AccountScreen";

const AppNavigator = () => {
  const Tab = createBottomTabNavigator();

  return (
    <NavigationContainer>
      <Tab.Navigator>
        <Tab.Screen name="Home" component={HomeScreen} />
        <Tab.Screen name="Account" component={AccountScreen} />
      </Tab.Navigator>
    </NavigationContainer>
  );
};

export default AppNavigator;

// [edit] App.js
import { StatusBar } from "expo-status-bar";
import React from "react";
import AppNavigator from "./navigation/AppNavigator";

export default function App() {
  return (
    <>
      <StatusBar style="dark" />
      <AppNavigator />
    </>
  );
}